org.apache.directory.shared.util
Class PropertiesUtils

java.lang.Object
  org.apache.directory.shared.util.PropertiesUtils

public final class PropertiesUtils
extends Object

A utility class used for accessing, finding, merging and macro expanding properties, on disk, via URLS or as resources.

Author:

Apache Directory Project

Method Summary

static void	discover(Properties keys, Properties[] sources, boolean haltOnDiscovery) Merges a set of properties from source Properties into a target properties instance containing keys.
static String	discover(String key, Properties[] sources, boolean haltOnDiscovery) Discovers a value within a set of Properties either halting on the first time the property is discovered or continuing on to take the last value found for the property key.
static Properties	findProperties(File dir, String filename) Create a new properties object and load the properties file if it exists relative to [dir]/[filename] or [dir]/[filename].properties.
static Properties	findUserProperties(String filename) Loads a properties object in a properties file if it exists relative to the filename ${user.home}.
static int	get(Hashtable<String,Object> ht, Object key, int defval) Gets a property or entry value from a hashtable and tries to transform whatever the value may be to an primitive integer.
static boolean	get(Properties props, String key, boolean defaultValue) Gets a String property as a boolean returning a defualt if the key is not present.
static byte	get(Properties props, String key, byte defaultValue)
static char	get(Properties props, String key, char defaultValue)
static long	get(Properties props, String key, long defaultValue)
static Properties	getProperties(Class<?> clazz, String path) Loads a properties file as a class resource if it exists and returns an empty Properties object otherwise.
static Properties	getProperties(ClassLoader classloader, String path) Loads a properties file as a CL resource if it exists and returns an empty Properties object otherwise.
static Properties	getProperties(File file) Creates a properties object and loads the properties in the file otherwise and empty property object will be returned.
static Properties	getStaticProperties(Class<?> ref) Load a properties from a resource relative to a supplied class.
static Properties	getStaticProperties(Class<?> ref, String path) Load properties from a resource relative to a supplied class and path.
static void	macroExpand(Properties expanded, Properties[] optionals) Expands out a set of property key macros in the following format ${foo.bar} where foo.bar is a property key, by dereferencing the value of the key using the original source Properties and other optional Properties.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

findUserProperties

public static Properties findUserProperties(String filename)

Loads a properties object in a properties file if it exists relative to the filename ${user.home}. If the file ${user.home}/[filename] does not exist then one last attempt to find the file is made if filename does not have a .properties extension. If so and ${user.home}/[filename].properties exists then it is loaded.

Parameters:

filename - the properties file name with or without an extension

Returns:

the user properties object

findProperties

public static Properties findProperties(File dir,
                                        String filename)

Create a new properties object and load the properties file if it exists relative to [dir]/[filename] or [dir]/[filename].properties.

Parameters:

dir - the base directory

filename - the full fine name or the base name w/o the extension

Returns:

the loaded properties object

getStaticProperties

public static Properties getStaticProperties(Class<?> ref)

Load a properties from a resource relative to a supplied class. First an attempt is made to locate a property file colocated with the class with the name [class].properties. If this cannot be found or errors result an empty Properties file is returned.

Parameters:

ref - a class to use for relative path references

Returns:

the static properties

getStaticProperties

public static Properties getStaticProperties(Class<?> ref,
                                             String path)

Load properties from a resource relative to a supplied class and path.

Parameters:

ref - a class to use for relative path references

path - the relative path to the resoruce

Returns:

the static properties

getProperties

public static Properties getProperties(File file)

Creates a properties object and loads the properties in the file otherwise and empty property object will be returned.

Parameters:

file - the properties file

Returns:

the properties object

getProperties

public static Properties getProperties(ClassLoader classloader,
                                       String path)

Loads a properties file as a CL resource if it exists and returns an empty Properties object otherwise.

Parameters:

classloader - the loader to use for the resources

path - the path to the resource

Returns:

the loaded or new Properties

getProperties

public static Properties getProperties(Class<?> clazz,
                                       String path)

Loads a properties file as a class resource if it exists and returns an empty Properties object otherwise.

Parameters:

clazz - the class to use for resolving the resources

path - the relative path to the resource

Returns:

the loaded or new Properties

macroExpand

public static void macroExpand(Properties expanded,
                               Properties[] optionals)

Expands out a set of property key macros in the following format ${foo.bar} where foo.bar is a property key, by dereferencing the value of the key using the original source Properties and other optional Properties. If the original expanded Properties contain the value for the macro key, foo.bar, then dereferencing stops by using the value in the expanded Properties: the other optional Properties are NOT used at all. If the original expanded Properties do NOT contain the value for the macro key, then the optional Properties are used in order. The first of the optionals to contain the value for the macro key (foo.bar) shorts the search. Hence the first optional Properties in the array to contain a value for the macro key (foo.bar) is used to set the expanded value. If a macro cannot be expanded because it's key was not defined within the expanded Properties or one of the optional Properties then it is left as is.

Parameters:

expanded - the Properties to perform the macro expansion upon

optionals - null or an optional set of Properties to use for dereferencing macro keys (foo.bar)

discover

public static String discover(String key,
                              Properties[] sources,
                              boolean haltOnDiscovery)

Discovers a value within a set of Properties either halting on the first time the property is discovered or continuing on to take the last value found for the property key.

Parameters:

key - a property key

sources - a set of source Properties

haltOnDiscovery - true if we stop on finding a value, false otherwise

Returns:

the value found or null

discover

public static void discover(Properties keys,
                            Properties[] sources,
                            boolean haltOnDiscovery)

Merges a set of properties from source Properties into a target properties instance containing keys. This method does not allow null overrides.

Parameters:

keys - the keys to discover values for

sources - the sources to search

haltOnDiscovery - true to halt on first find or false to continue to last find

get

public static boolean get(Properties props,
                          String key,
                          boolean defaultValue)

Gets a String property as a boolean returning a defualt if the key is not present. In any case, true, on, 1 and yes strings return true and everything else returns

Parameters:

props - the properties to get the value from

key - the property key

defaultValue - the default value to return if key is not present

Returns:

true defaultValue if property does not exist, else return true if the String value is one of 'true', 'on', '1', 'yes', otherwise false is returned

get

public static int get(Hashtable<String,Object> ht,
                      Object key,
                      int defval)

Gets a property or entry value from a hashtable and tries to transform whatever the value may be to an primitive integer.

Parameters:

ht - the hashtable to access for the value

key - the key to use when accessing the ht

defval - the default value to use if the key is not contained in ht or if the value cannot be represented as a primitive integer.

Returns:

the primitive integer representation of a hashtable value

get

public static long get(Properties props,
                       String key,
                       long defaultValue)

get

public static byte get(Properties props,
                       String key,
                       byte defaultValue)

get

public static char get(Properties props,
                       String key,
                       char defaultValue)